scholarly journals Developing an Automated Gas Sampling Chamber for Measuring Variations in CO2 Exchange in a Maize Ecosystem at Night

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6117
Author(s):  
Chaoqun Li ◽  
Wenting Han ◽  
Manman Peng ◽  
Mengfei Zhang
Keyword(s):  
Control System ◽  
Performance Test ◽  
Net Ecosystem Exchange ◽  
Co2 Exchange ◽  
Air Humidity ◽  
Closed Chamber ◽  
Humidity Control ◽  
Chamber Volume ◽  
Measuring Period ◽  
Relative Change

The measurement of net ecosystem exchange (NEE) of field maize at a plot-sized scale is of great significance for assessing carbon emissions. Chamber methods remain the sole approach for measuring NEE at a plot-sized scale. However, traditional chamber methods are disadvantaged by their high labor intensity, significant resultant changes in microclimate, and significant impact on the physiology of crops. Therefore, an automated portable chamber with an air humidity control system to determinate the nighttime variation of NEE in field maize was developed. The chamber system can automatically open and close the chamber, and regularly collect gas in the chamber for laboratory analysis. Furthermore, a humidity control system was created to control the air humidity of the chamber. Chamber performance test results show that the maximum difference between the temperature and humidity outside and inside the chamber was 0.457 °C and 5.6%, respectively, during the NEE measuring period. Inside the chamber, the leaf temperature fluctuation range and the maximum relative change of the maize leaf respiration rate were −0.3 to 0.3 °C and 23.2015%, respectively. We verified a series of measurements of NEE using the dynamic and static closed chamber methods. The results show a good common point between the two measurement methods (N = 10, R2 = 0.986; and mean difference: ΔCO2 = 0.079 μmol m−2s−1). This automated chamber was found to be useful for reducing the labor requirement and improving the time resolution of NEE monitoring. In the future, the relationship between the humidity control system and chamber volume can be studied to control the microclimate change more accurately.

scholarly journals Neuro-fuzzy humidity control for white oyster mushroom in a closed plant production system

2021 ◽  
Vol 905 (1) ◽  
pp. 012066
Author(s):  
D K Anta ◽  
Sandra ◽  
Y Hendrawan
Keyword(s):  
Control System ◽  
Relative Humidity ◽  
Production System ◽  
Performance Test ◽  
Plant Production ◽  
Oyster Mushroom ◽  
Mushroom Cultivation ◽  
Humidity Control ◽  
Steady State Condition ◽  
Neuro Fuzzy

Abstract Oyster mushrooms grow optimally in relative humidity of 80-90%. As a tropical country, Indonesia is very suitable for oyster mushroom cultivation, but relative humidity must be controlled. The usual effort is ineffective by spraying water to mushroom inside kumbung (mushroom cultivation building) every morning and evening. A building called a Closed Plant Production System (CPPS) equipped with a control system needs to be developed as a solution. The purpose of this study was to design and do a performance test of a neuro-fuzzy based relative humidity control system inside CPPS for white oyster mushroom (Pleurotus ostreatus) cultivation. The main components consist of Arduino Mega 2560 microcontroller, SHT11 sensor, and diaphragm pump connects with mist nozzle as an actuator. The performance test was carried out by running neuro-fuzzy based control system and giving disturbance inside CPPS room. As a result, this control system was able to reach a steady-state condition within 5 minutes. The highest relative humidity error was 0.73%, and the lowest error was 0.09%—the recovery rate of relative humidity inside CPPS when disturbed was 2.25% per minute.

scholarly journals Design of adaptive humidity control system based on ultrasonic humidification in room temperature

2021 ◽  
Vol 1976 (1) ◽  
pp. 012049
Author(s):  
Jun Deng ◽  
Limin Chang ◽  
Gang Cui ◽  
Ping Wang ◽  
Yongji Lu
Keyword(s):  
Control System ◽  
Room Temperature ◽  
Humidity Control

Open-Source Real-Time Robot Operation and Control System for Highly Dynamic, Modular Machines

2013 ◽  
Author(s):  
Andrew Peekema ◽  
Daniel Renjewski ◽  
Jonathan Hurst
Keyword(s):  
Control System ◽  
Open Source ◽  
Real Time ◽  
High Frequency ◽  
Performance Test ◽  
Frequency Control ◽  
Human Robot Interaction ◽  
Sensors And Actuators ◽  
Key Innovation ◽  
Hard Real Time

The control system of a highly dynamic robot requires the ability to respond quickly to changes in the robot’s state. This type of system is needed in varying fields such as dynamic locomotion, multicopter control, and human-robot interaction. Robots in these fields require software and hardware capable of hard real-time, high frequency control. In addition, the application outlined in this paper requires modular components, remote guidance, and mobile control. The described system integrates a computer on the robot for running a control algorithm, a bus for communicating with microcontrollers connected to sensors and actuators, and a remote user interface for interacting with the robot. Current commercial solutions can be expensive, and open source solutions are often time consuming. The key innovation described in this paper is the building of a control system from existing — mostly open source — components that can provide realtime, high frequency control of the robot. This paper covers the development of such a control system based on ROS, OROCOS, and EtherCAT, its implementation on a dynamic bipedal robot, and system performance test results.

The Design of Automatic Control System for Greenhouse Based on Microcontroller

2013 ◽  
Vol 446-447 ◽  
pp. 1188-1192
Author(s):  
Xin Yu Sun
Keyword(s):  
Control System ◽  
Automatic Control ◽  
Performance Test ◽  
Scientific Basis ◽  
Automatic Control Theory ◽  
Output Efficiency ◽  
Automation Control ◽  
New Situation ◽  
Greenhouse Control ◽  
High Output

Recently, with the rapid agricultural application progress in China, greenhouse control issues have been better addressed. The greenhouse control technology, as an emerging technology, is increasingly being widespread attended, and is gradually walking in the direction of constructing good quality, high output efficiency agricultural systems. In this new situation, we need to carry out market research, carefully research the greenhouse automatic control theory based on SCM technology, and design automation control system with best effect. The performance test result shows: This new system has a good usable performance, while related technology can provide a scientific basis for further research in the future. Keywords.Microcontroller; greenhouse automatic control.

scholarly journals Greenhouse gas flux measurements in a forestry-drained peatland indicate a large carbon sink

2011 ◽  
Vol 8 (11) ◽  
pp. 3203-3218 ◽  
Author(s):  
A. Lohila ◽  
K. Minkkinen ◽  
M. Aurela ◽  
J.-P. Tuovinen ◽  
T. Penttilä ◽  
...  
Keyword(s):  
Carbon Sink ◽  
Accumulation Rate ◽  
Peat Soil ◽  
Net Ecosystem Exchange ◽  
Flux Measurement ◽  
Co2 Exchange ◽  
Co2 Uptake ◽  
Flux Measurements ◽  
Ch4 And N2o ◽  
Carbon Dioxide Co2

Abstract. Drainage for forestry purposes increases the depth of the oxic peat layer and leads to increased growth of shrubs and trees. Concurrently, the production and uptake of the greenhouse gases carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) change: due to the accelerated decomposition of peat in the presence of oxygen, drained peatlands are generally considered to lose peat carbon (C). We measured CO2 exchange with the eddy covariance (EC) method above a drained nutrient-poor peatland forest in southern Finland for 16 months in 2004–2005. The site, classified as a dwarf-shrub pine bog, had been ditched about 35 years earlier. CH4 and N2O fluxes were measured at 2–5-week intervals with the chamber technique. Drainage had resulted in a relatively little change in the water table level, being on average 40 cm below the ground in 2005. The annual net ecosystem exchange was −870 ± 100 g CO2 m−2 yr−1 in the calendar year 2005, indicating net CO2 uptake from the atmosphere. The site was a small sink of CH4 (−0.12 g CH4 m−2 yr−1) and a small source of N2O (0.10 g N2O m−2 yr−1). Photosynthesis was detected throughout the year when the air temperature exceeded −3 °C. As the annual accumulation of C in the above and below ground tree biomass (175 ± 35 g C m−2) was significantly lower than the accumulation observed by the flux measurement (240 ± 30 g C m−2), about 65 g C m−2 yr−1 was likely to have accumulated as organic matter into the peat soil. This is a higher average accumulation rate than previously reported for natural northern peatlands, and the first time C accumulation has been shown by EC measurements to occur in a forestry-drained peatland. Our results suggest that forestry-drainage may significantly increase the CO2 uptake rate of nutrient-poor peatland ecosystems.

Sign in / Sign up

Export Citation Format

Share Document